通过高缩来刺激兰化元素的电子移位,以促进电催化水分裂
Yong Jiang1, Zhong Liang1, Jin-Cheng Liu1
1Tianjin Key Lab for Rare Earth Materials and Applications, Center for Rare Earth and Inorganic Functional Materials, Haihe Laboratory of Sustainable Chemical Transformations, Smart Sensing Interdisciplinary Science Center, School of Materials Science and Engineering, National Institute for Advanced Materials, Nankai University, Tianjin 300350, P. R. China.
ACS nano
|July 9, 2024
概括
将稀土元素引入高合金 (HEAs) 优化了催化剂性能. 改性HEAs对和氧演化反应具有增强的电催化活性,提高了水分化的效率.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 高合金 (HEAs) 在催化中表现有前途,但遭受过度吸附,阻碍效率.
- 在HEAs中优化吸附强度对于增强催化活性至关重要.
- 稀土 (RE) 元素可以通过与多个活跃站点相互作用来修改HEA属性.
研究的目的:
- 研究将稀土 (RE) 元素,特别是 (Ce) 纳入高合金 (HEAs) 的效果,以调整吸附强度和提高催化效率.
- 为电催化应用合成和表征Ce-修饰的HEAs,重点关注演变反应 (HER) 和氧演变反应 (OER).
- 用实验和计算方法阐明增强催化性能背后的基本机制.
主要方法:
- 六角密封PtRuFeCoNiZn-Ce/C高合金的合成.
- 在酸性和性介质中对演化反应 (HER) 和氧演化反应 (OER) 的电催化性能评估.
- 在现场减弱的全反射红外光谱和密度函数理论 (DFT) 计算.
主要成果:
- 合成的PtRuFeCoNiZn-Ce/C HEAs对超低超潜的HER和OER表现出极好的电催化活性.
- 实现了HER的4mV和OER的156mV (10mA cm-2在0.5M H2SO4),以及HER的7mV和OER的132mV (10mA cm-2在1.0M KOH).
- 使用这些HEA组装的水电解电池仅需要1.43V才能达到10mA cm-2,显著超过未经修改的PtRuFeCoNiZn/C.
结论:
- 将RE元素 (Ce) 引入HEAs,通过4f电子移位和增强的电子交换,优化吸附强度.
- 由于RE和活性位点之间的电子阴性差异,表面二极管的形成进一步增强了中间吸附.
- 这项研究为设计用于能源转换应用的基于HEA和RE的高性能电催化剂提供了一个新的策略.
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